Data analysis презентация

OVERVIEW
Qualitative and quantitative
Simple quantitative analysis
Simple qualitative analysis
Tools to support data analysis
Theoretical frameworks: grounded theory,
distributed cognition, activity theory
Presenting the findings: rigorous notations,
stories, summaries

SCALES OF MEASUREMENT
into a non-
Many people are confused about what type of analysis to use on a set of data and the relevant forms of pictorial presentation or data display. The decision is based on the scale of measurement of the data. These scales are nominal, ordinal and numerical.
Nominal scale
A nominal scale is where:
the data can be classified numerical or named categories, and
the order in which these categories can be written or asked is arbitrary.
Ordinal scale
An ordinal scale is where:
the data can be classified into non-numerical or named categories
an inherent order exists among the response categories.
Ordinal scales are seen in questions that call for ratings of quality (for example, very good, good, fair, poor, very poor) and agreement (for example, strongly agree, agree, disagree, strongly disagree).
Numerical scale
A numerical scale is:
where numbers represent the possible response categories
there is a natural ranking of the categories zero on the scale has meaning
there is a quantifiable difference within categories and between consecutive categories.

When using a quantitative methodology, you are normally testing theory through the testing of a hypothesis.
In qualitative research, you are either exploring the application of a theory or model in a different
context or are hoping for a theory or a model to emerge from the data. In other words, although you may have some ideas about your topic, you are also looking for ideas, concepts and attitudes often from experts or practitioners in the field.

GRAPHICAL REPRESENTATIONS
give overview of data
Number of errors made
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
1 3 5 7 9 11 13 15 17
User
Number of errors made
Internet use
< once a day
once a day once a week
2 or 3 times a week once a month
Number of errors made
10
8
6
4
2
0
0
5
15
20
10
User
Number of errors made

Visualizing log data
Interaction profiles of players in online game
Log of web page activity

QUALITATIVE ANALYSIS
"Data analysis is the process of bringing order, structure and meaning to the mass of collected data. It is a messy, ambiguous, time- consuming, creative, and fascinating process. It does not proceed in a linear fashion; it is not neat.
Qualitative data analysis is
a search for general statements about relationships among categories of data."
Marshall and Rossman, 1990:111
Hitchcock and Hughes take this one step further:
"…the ways in which the researcher moves from a description of what is the case to an explanation of why what is the case is the case."
Hitchcock and Hughes 1995:295

Simple qualitative analysis
Unstructured - are not directed by a script. Rich but not replicable.
Structured - are tightly scripted, often like a questionnaire. Replicable but may lack richness.
Semi-structured - guided by a script but interesting issues can be explored in more depth. Can provide a good balance between richness and replicability.

Simple qualitative analysis
Recurring patterns or themes
Emergent from data, dependent on observation framework if used
Categorizing data
Categorization scheme may be emergent or pre-specified
Looking for critical incidents
Helps to focus in on key events

TOOLS TO SUPPORT DATA
ANALYSIS
Spreadsheet – simple to use, basic graphs
Statistical packages, e.g. SPSS
Qualitative data analysis tools
Categorization and theme-based analysis, e.g. N6
Quantitative analysis of text-based data

Theoretical frameworks for
qualitative analysis
Basing data analysis around theoretical frameworks provides further insight
Three such frameworks are:
Grounded Theory
Distributed Cognition
Activity Theory

Grounded Theory
Aims to derive theory from systematic analysis of data
Based on categorization approach (called here ‘coding’)
Three levels of ‘coding’
Open: identify categories
Axial: flesh out and link to subcategories
Selective: form theoretical scheme
Researchers are encouraged to draw on own theoretical backgrounds to inform analysis

Distributed Cognition
The people, environment & artefacts are regarded as one cognitive system
Used for analyzing collaborative work
Focuses on information propagation & transformation

Activity Theory
Explains human behavior in terms of our practical activity with the world
Provides a framework that focuses analysis around the concept of an ‘activity’ and helps to identify tensions between the different elements of the system
Two key models: one outlines what constitutes an ‘activity’; one models the mediating role of artifacts

Individual model

Engeström’s (1999) activity
system model